1. jika fungsi f (x) = 4x+5 dengan g(x) = 2x-3 / 4x+7 maka nilai dari (gof)-1 (1) adalah... 2. jika f (x) = 5x+2 dan (fog) 0 =32 - 20x. maka boleh dari g-1 (x)

1.f-1(x) = x-5/4
   f-1(1) =1-5/4
   f-1(1) = -1
   g(-1) = 2(-1)-3/4(-1)+7
   g(-1) = -5/-11
            = 5/11 
   maaf kalau salah 

Fungsi invers

1.
f(x) = 4x + 5
g(x)= (2x-3)/(4x+7)

gof(x)= g { f(x)} = [ 2(4x+5) - 3  ] / [ 4(4x+5) + 7 ]
gof(x) = [ 8x+10-3 ] / [ 16x+20+7 ]
gof(x)= (8x +7)/ (16x + 27)
.
(gof)⁻¹ {(8x+7)/(16x+27) = x
(gof)⁻¹ (1) = ...

(8x + 7) /(16x + 27) = 1
1(16x + 27) = 8x + 7
16x  + 27 = 8x + 7
16x -8x = 7 - 27
8x = -20
x = -20/8
x = - 5/4

2.
f(x)=5x+2

fog(x) = 32 - 20x
f {g(x)} = 32 - 20x
5. g(x) +2 = 32 - 20x
5. g(x)= -20x + 32 -2
5. g(x)= -20x + 30
g(x)= -4x + 6
y = -4x + 6
4x = 6-y
x = 1/4 (6 -y)
g⁻¹(x)= 1/4 (6 - x)